This 9-week study was designed to determine whether a commercial cognitive-behavioral training program could effectively reduce overt aggression behavior in Chinese young male violent offenders. Sixty-six participants were randomly assigned to receive routine intervention alone (control group) or routine intervention plus Williams LifeSkills Training (WLST group) in a 1:1 ratio. The primary outcome was change scores on the Modified Overt Aggression Scale (MOAS) from baseline to one week following end of training. Secondary outcomes were change scores on the Barratt Impulsiveness Scale-11 (BIS-11) and Cook–Medley Hostility Scale (CMHS). There were significant between-group differences in change of MOAS total score (P < .001) and all sub-scores (Ps < .01) except aggression against property. Between-group differences were also observed in change of BIS-11 and CMHS total score (Ps < 0.05). All results favored the WLST group. These findings suggest WLST has the potential to be an effective intervention to reduce overt aggressive behavior in young male violent offenders.